Dyslexia and other symbolic dysfunctions, not elsewhere classified (R48)
The ICD-10 code section R48 is used to classify dyslexia and other symbolic dysfunctions that do not fit into other specific categories. These codes help identify and document conditions affecting the ability to process language, symbols, or related cognitive functions.
This section includes R48.0 for dyslexia and alexia, which covers difficulties with reading and language, sometimes referred to by synonyms like phonological dyslexia, surface dyslexia, or cortical alexia. R48.1 identifies agnosia, a condition where individuals lose the ability to recognize sensory information despite intact senses, with common forms including auditory or tactile agnosia. The code R48.2 covers apraxia, representing impairments in purposeful movement such as motor or speech apraxia. Visual agnosia, coded as R48.3, relates to difficulties recognizing visual objects, including conditions like prosopagnosia or Balint syndrome. Other symbolic dysfunctions, such as agraphia or dyscalculia, are grouped under R48.8, while unspecified symbolic dysfunctions fall under R48.9. Using these codes accurately helps link clinical symptoms like cluttering, sensory agnosia, or echolalia to precise diagnostic categories.
Instructional Notations
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- specific developmental disorders of scholastic skills F81
Clinical Terms
The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.
Agnosia
Loss of the ability to comprehend the meaning or recognize the importance of various forms of stimulation that cannot be attributed to impairment of a primary sensory modality. Tactile agnosia is characterized by an inability to perceive the shape and nature of an object by touch alone, despite unimpaired sensation to light touch, position, and other primary sensory modalities.
Agraphia
Loss or impairment of the ability to write (letters, syllables, words, or phrases) due to an injury to a specific cerebral area or occasionally due to emotional factors. This condition rarely occurs in isolation, and often accompanies APHASIA. (From Adams et al., Principles of Neurology, 6th ed, p485; APA, Thesaurus of Psychological Index Terms, 1994)
Alexia, Pure
Loss of the power to comprehend written materials despite preservation of the ability to write (i.e., alexia without agraphia). This condition is generally attributed to lesions that disconnect the visual cortex of the non-dominant hemisphere from language centers in the dominant hemisphere. This may occur when a dominant visual cortex injury is combined with underlying white matter lesions that involve crossing fibers from the occipital lobe of the opposite hemisphere. (From Adams et al., Principles of Neurology, 6th ed, p483)
Dyscalculia
Impaired ability in numerical concepts. These inabilities arise as a result of primary neurological lesion, are syndromic (e.g., GERSTMANN SYNDROME ) or acquired due to brain damage.
Dyslexia
A cognitive disorder characterized by an impaired ability to comprehend written and printed words or phrases despite intact vision. This condition may be developmental or acquired. Developmental dyslexia is marked by reading achievement that falls substantially below that expected given the individual's chronological age, measured intelligence, and age-appropriate education. The disturbance in reading significantly interferes with academic achievement or with activities of daily living that require reading skills. (From DSM-IV)
Dyslexia, Acquired
A receptive visual aphasia characterized by the loss of a previously possessed ability to comprehend the meaning or significance of handwritten words, despite intact vision. This condition may be associated with posterior cerebral artery infarction (INFARCTION, POSTERIOR CEREBRAL ARTERY) and other BRAIN DISEASES.
Echolalia
Involuntary (parrot-like), meaningless repetition of a recently heard word, phrase, or song. This condition may be associated with transcortical APHASIA; SCHIZOPHRENIA; or other disorders. (From Adams et al., Principles of Neurology, 6th ed, p485)
Gerstmann Syndrome
A disorder of cognition characterized by the tetrad of finger agnosia, dysgraphia, DYSCALCULIA, and right-left disorientation. The syndrome may be developmental or acquired. Acquired Gerstmann syndrome is associated with lesions in the dominant (usually left) PARIETAL LOBE which involve the angular gyrus or subjacent white matter. (From Adams et al., Principles of Neurology, 6th ed, p457)
Prosopagnosia
The inability to recognize a familiar face or to learn to recognize new faces. This visual agnosia is most often associated with lesions involving the junctional regions between the temporal and occipital lobes. The majority of cases are associated with bilateral lesions, however unilateral damage to the right occipito-temporal cortex has also been associated with this condition. (From Cortex 1995 Jun;31(2):317-29).
